Question

What is the center of the circle given by the equation (x-3)2 + (y-9)2 = 16?

A. (-9,-3)
B. (-3,-9)
C. (3,9)
D. (9,3)

Answer 1

C

Explanation:

(x-a)^2 + (y-b)^2 = r^2

(a,b) = Center

r = radius

SO...

That means the center of the circle " (x-3)^2 + (y-9)^2 = 16" is...

(3,9) (C)

Answer 2

The center is (3,9) and the radius is 4

Explanation:

We can write the equation for a circle as

(x-h)^2 + (y-k)^2 = r^2

Where (h,k) is the center and r is the radius

(x-3)^2 + (y-9)^2 = 4^2

The center is (3,9) and the radius is 4